Excipients play a crucial role in tablet formulation, serving various functions that ensure the quality, efficacy, and manufacturability of the final product. Here are some key roles of excipients in tablet formulation:

1. Binders

• Function: Binders help in holding the ingredients in a tablet together, ensuring that the tablet remains intact after compression.
• Examples: Starch, gelatin, and polyvinylpyrrolidone (PVP).

2. Fillers/Diluents

• Function: Fillers add volume to tablets, especially when the active drug is in very small quantities, to make the tablet a manageable size.
• Examples: Lactose, microcrystalline cellulose, and mannitol.

3. Disintegrants

• Function: Disintegrants facilitate the breakup of the tablet after oral administration to ensure the active ingredient is released for absorption.
• Examples: Sodium starch glycolate, croscarmellose sodium, and crospovidone.

4. Lubricants

• Function: Lubricants prevent the tablet and its ingredients from sticking to the equipment during production and reduce friction during tablet ejection.
• Examples: Magnesium stearate, stearic acid, and talc.

5. Glidants

• Function: Glidants improve the flow properties of the powder or granules, ensuring uniform filling of the die cavity during tablet manufacturing.
• Examples: Colloidal silicon dioxide, talc, and magnesium carbonate.

6. Coatings

• Function: Coatings protect the tablet from environmental factors (such as moisture and light), mask unpleasant tastes or odors, and sometimes control the release of the drug.
• Examples: Hydroxypropyl methylcellulose (HPMC), ethyl cellulose, and various sugar coatings.

7. Colorants

• Function: Colorants improve the aesthetic appearance of the tablet and can help in identifying different medications.
• Examples: Titanium dioxide, iron oxide pigments, and FD&C dyes.

8. Flavoring Agents

• Function: Flavoring agents mask the unpleasant taste of the active drug, improving patient compliance.
• Examples: Artificial sweeteners like aspartame, and natural flavors like mint and vanilla.

9. Preservatives

• Function: Preservatives protect the tablet from microbial contamination and degradation.
• Examples: Methylparaben, propylparaben, and benzalkonium chloride.

10. Controlled Release Excipients

• Function: These excipients help in modifying the release rate of the active ingredient from the tablet, providing a sustained or delayed release profile.
• Examples: Ethylcellulose, polymethacrylates, and certain types of hydrogels.